燃烧中吸附剂捕集铅的实验研究  

Experimental Study on Lead Capture by Sorbents During Combustion

作　　者：张小锋[1] 姚强[1] 宋蔷[1] 李水清[1] 

机构地区：[1]清华大学热科学与动力工程教育部重点实验室,北京市海淀区100084

出　　处：《中国电机工程学报》2008年第2期61-65,共5页Proceedings of the CSEE

基　　金：国家重点基础研究发展规划基金项目(2002CB211606)。~~

摘　　要：使用一维炉实验台对氧化铝、氢氧化钙和高岭土3种吸附剂对铅的捕集进行了实验研究。铅以醋酸铅溶液的形式通过空气雾化引入到液化石油气燃烧区,吸附剂由压缩空气携带从1473K喷入炉内。按照美国EPA标准方法使用Andersen撞击器对颗粒物进行等动量采样,采用电感耦合等离子发射光谱仪(ICP-AES)测量样品中铅的含量。结果表明:亚微米范围的铅未被吸附剂所捕集,仍以PbO或PbCl2颗粒存在,微米范围的铅被吸附剂捕集形成。高岭土对铅的捕集明显好于其他吸附剂,这是由于高岭土与氧化铝、氢氧化钙相比,对Pb有更强的化学吸附作用。高岭土给料量为10g/h时大部分铅分布在亚微米范围,给料量为20g/h时铅呈双峰分布,给料量为60g/h时大部分铅被捕集转移到微米范围。氯元素对高岭土捕集铅有很强的抑制作用,这种抑制很可能是因为高岭土活性位Al2O3·2Si2O与PbCl2的反应性要大大低于Al2O3·2Si2O与PbO的反应性。Lead capture by three sorbents： alumina, calcium hydroxide and kaolinite, were investigated experimentally using a laboratory one-dimension furnace. Aqueous solution of lead acetate was introduced into furnace through a liquefied petroleum gas flame via air atomization. Sorbents were introduced into furnace by compressed air at 1473 K. Isokinetic particle sampling was done using Thermo Andersen impactor according to standard method of U.S. EPA. Lead content in samples was measured by inductively coupled plasma atomic emission spectrometry （ICP-AES）. The results show that： Lead in submicron size range is not captured by sorbents and still exists in the form of PbO or PbCl2 particles; lead in micron size range is formed by sorbents adsorption. Effect of lead capture by kaolinite is much better than by other sorbents. The reason is that kaolinite has higher chemical adsorption reaction with molecules of PbO vapor than alumina and calcium hydroxide. Majority of lead remains in submicron size range when kaolinite feed rate is 10 g/h, lead presents a bimodal particle size distribution when kaolinte feed rate is 20 g/h, and most of lead is captured and transferred to micron size range when kaolinite feed rate is 60 g/h. Chlorine has highly inhibition effect to lead capture by kaolinite, the possible reason is that the reaction between active sites Al2O3·2Si2O and PbCl2 was much less active than reaction between Al2O3·2Si2O and PbO.

关 键 词：铅 吸附剂 捕集 颗粒物 粒径分布 

分 类 号：TK16[动力工程及工程热物理—热能工程] X513[环境科学与工程—环境工程]